On 09/13/2014 02:48 AM, Allan Irving wrote:
First thing, heat + plastic. Bad idea? Any suggestions as to how to place or manipulate the heat sink and CPU to reduce melting or danger?
"Plastic" is a term far too general. Most Lego blocks are made of ABS¹, and its properties vary depending on the precise formula employed by the manufacturer. For an example of common parameters see ². Unless you intend to ask Lego's ABS supplier for the precise parameters of their variant of ABS, I would suggest placing the heatsink, CPU, and GPU as far away as possible from the sides of the enclosure. I would also suggest placing an additional temperature sensor at the Lego bricks closest to the heatsink and use it to limit processor speeds if necessary.
¹ http://lego.wikia.com/wiki/Acrylonitrile_Butadiene_Styrene ² http://www.dynalabcorp.com/technical_info_abs.asp
Cheers,